장우선 교수

Abstract Aiming toward a sustainable energy era, the design of efficient photocatalysts for water splitting by engineering their band properties has been actively studied. One promising avenue for the band engineering of active photocatalysts is the use of solid-solution alloying. However, the enormous possible configurations of multicomponent alloys hinders the experimental screening of this multidimensional material space, providing an opportunity for machine learning (ML) approaches to help a

Despite the ubiquitous nature of the Peltier effect in low-dimensional thermoelectric devices, the influence of finite temperature on the electronic structure and transport in the Dirac heterointerfaces of the few-layer graphene and layered tetradymite, Sb 2 Te 3 (which coincidently have excellent thermoelectric properties) are not well understood. In this work, using the first-principles density-functional theory calculations, we investigate the detailed atomic and electronic structure of these

Recently, a subclass of binary perovskite-structured metal trioxides, such as WO 3 and MoO 3, have been propounded for many key optoelectronic applications due to their proper band edge positions and appropriate band gap sizes. Unlike their superclass perovskites, the structure–property relationship for these binary metal trioxides is less apparent, given that they suffer from much larger structural deformities within the octahedra. In this work, by using first-principles density-functional theo

Many different forms of mechanical and structural deformations have been employed to alter the electronic structure of various modern two-dimensional (2D) nanomaterials. Given the recent interest in the new class of 2D nanomaterials - phosphorene, here we investigate how the rotational strain-dependent electronic properties of low-dimensional phosphorene may be exploited for technological gain. Here, using first-principles density-functional theory, we investigate the mechanical stability of twi

Exploring beyond monoelemental and binary two-dimensional (2D) nanomaterials is an important step to further engineer and functionalize well-known 2D nanomaterials for the next-generation technologies. In this work, using state-of-the-art first-principles electronic structure calculations and statistical sampling of structural configurations, we examine the influence of anionic exchange in two monolayer group IV (namely, Ge- and Sn-based) monochalcogenides. Using chemical bonding analysis, we de

In the recent era of green and sustainable energy, the demand for effective and efficient energy harvesting has dramatically increased. Piezoelectric energy harvesting, which converts mechanical energy into electrical energy, is considered a viable strategy to achieve this goal. Janus-type nanomaterial, a noncentrosymmetric material with different elemental species in the upper and lower atomic layers, has gained interest due to its exotic properties compared to conventional bulk and symmetric m

atomistic thermodynamics approach coupled to implicit solvation models and Gibbs-Wulff shape constructions, we demonstrate that this absence of predictive power stems from the limitation of equilibrium thermodynamics. By re-tracing and carefully addressing with a more realistic chemical potential definition, we illustrate this shortcoming can be overcome and afford a more rational route to size-engineer and shape-design highly-functional group 5 tetradymite nanoparticles for targeted application

We present the photoinduced terahertz responses of topological insulators Bi2Se3. The photoconductance sign is determined by the competition between the topological surface state and the bulk response in n-type, p-type and bulk-insulating Bi2Se3.

Highly reversible lithium (Li) plating/stripping in zero-excess Li metal batteries (ZE-LMBs) demands lithiophilic current collectors to suppress Li dendrite formation and Li pulverization. Although Li-alloyable metals have been recognized as lithiophilic substrates, their structural and interfacial stability over cycling are still poorly understood. Here, we present a bimetallic lithiophilic current collector through sequential coatings of platinum (Pt) and silver (Ag). Experimental and computat

An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Graphene and topological insulator (TI) host two-dimensional (2D) Dirac surface plasmon at the terahertz frequency range. We observed unconventional density-dependence of 2D topological Dirac plasmon upon in proximity to the monolayer graphene.